why is Madame Loisel unhappy with her life at the beginning of the story?

Madame Loisel

was as unhappy as though she had married beneath her; for women have no caste or class, their beauty, grace, and charm serving them for birth or family, their natural delicacy, their instinctive elegance, their nimbleness of wit, are their only mark of rank, and put the slum girl on a level with the highest lady in the land.

Although her birth was relatively humble—she is the daughter of artisans—Mathilde feels as though she is destined for a more exceptional life. Though she possesses no money and no real connections, as a young woman she dreamed of marrying an important man, a "man of wealth and distinction," because she is beautiful and charming and feels as though this ought to be qualification enough. In short, she dreamed big but was eventually "married off to a little clerk" who works for the government's department of education: hardly a glamorous match. Her simple life is not the exciting one for which she'd hoped, and she laments the "poorness of her house," worn furniture, and her one young servant girl. She dreams of "delicate meals, gleaming silver, tapestries peopling the walls," and she is dissatisfied with a life that provides none of these. Even when her husband procures an invitation to a fancy party, Mathilde is unhappy because she has nothing nice enough to wear.